Toy Hauler
Grand Design RV Momentum M-Class 388m
Compare specs across all model years (2015–2018)
4
Model Years
8
Sleeps
41' 9"
Length
18,250
Avg GVWR
Our Recommendation
Which Year Should You Buy?
2018 Momentum M-Class 388m
Best Choice
Highest Mint Score (30.4). Most recent model year with latest updates.
What Changed Year-Over-Year
2017
2018
Larger Fresh Tank
Fresh water capacity changed from 117 to 157 gallons.
2016
2017
Weight Increase
GVWR increased from 18,000 to 18,500 lbs (500 lbs heavier).
2015
2016
Capacity Upgrade
Sleeping capacity increased from 7 to 8 with layout improvements.
All Model Years
Best Value
2018
2018 Grand Design RV Momentum M-Class 388m
30.4
18,500 lbs GVWR
2,800 lbs Hitch
41' 9"
Sleeps 8
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2017
2017 Grand Design RV Momentum M-Class 388m
29.4
18,500 lbs GVWR
2,800 lbs Hitch
41' 9"
Sleeps 8
↑ 500 lbs heavier than 2016
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Check Towing
2016
2016 Grand Design RV Momentum M-Class 388m
29.4
18,000 lbs GVWR
2,900 lbs Hitch
41' 9"
Sleeps 8
↑ Sleeps 1 more than 2015
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Check Towing
2015
2015 Grand Design RV Momentum M-Class 388m
28.9
18,000 lbs GVWR
2,900 lbs Hitch
41' 9"
Sleeps 7
Original model year
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Can Your Vehicle Tow the Momentum M-Class 388m?
Enter your truck specs to see if any of these model years fit your towing capacity—and which year gives you the most safety margin.
Tip: Click a year to see the full specs, tow guidance, and recommended gear for that model year.
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